fragmental

I'm trying to replace a fuel pump on a '92 4.0L i6. I've removed the hoses and electrical connector from the old pump, and removed the lock ring. Before removing the old pump, I decided to see if I could get the lock ring back on, to see what it would be like to secure the new pump. For whatever reason the exterior of the pump won't sit flush against the gasket/tank. I have the two notches in the right spot, it just doesn't want to lay flat.

It looks kind of like in this video, at the ~7min mark. https://www.youtube.com/watch?v=MC2-...outu.be&t=7m2s

jmu427

I had the same situation on my 92 recently. I just had to shift the whole assembly around to get the ring started on one side then roll it to fully seat it. It didn't kook like it would work at first either, but it got seated after some time messing with it.

fragmental

The reason the old pump wouldn't sit flat is that there is a rubber grommet that fits on the end of the pump assembly and goes into a (hole?) in the bottom of the fuel tank. I couldn't see this because I hadn't fully dropped the tank. I finally dropped the tank and could see this pretty clearly.

However, my new pump assembly wouldn't fit, even when it was sitting properly in the (hole) inside the tank. It was supposed to be an oem style part, but it looked a little different. The pump itself was bigger, the hose was longer, and the tubes were bent at slight different angles. It was an airtex e7072s. I checked all of the parts stores and they all had the same style part for my year. Even the replacement without the assembly looked the same.

However, I checked a 1995 jeep cherokee pump and that pump did match the assembly from my 92. I couldn't find a replacement assembly for it, but decided to keep the old assembly. I just changed out the pump, the sock, some hoses, and the o-ring. I don't know if the parts stores all just have the wrong style of assembly/pump for my model year or if the tank was changed out at some point before I got the vehicle.

Sadly though, when I got the whole thing back together it still didn't start.

DFlintstone

Thank-you! That should darn near be a "sticky". I had figured out there HAD to be something, I just couldn't nail down what it was. I put it out to the forum a couple of times..... ended up "swinging at smoke" (again). Much thanks again for that crucial bit of info!

fragmental

Hey. You're welcome.

I figured out what was keeping mine from starting. The throttle body was all gummed up, and keeping it from getting air. It would kind of sputter occasionally, but that was it. After cleaning the throttle body, it started and ran no problem.

I've cleaned the throttle body a long time ago, I just didn't think of it as a possible cause in this case.

DFlintstone

Are you posting in the correct thread? The fuel pump and the throttle body are about 8 feet apart!

You might want to click on my signature and look at Cruiser's tips. Actually it's your IAC that lets air through while you crank it. Something to clean as well.

fragmental

Yeah, I know it's kind of off topic for the title of the thread, but I was in the process of trying to get the car to start. I thought it was the fuel pump, but the car exhibited the same systems after replacing the pump. It was only after cleaning the throttle body that it actually started up and ran.

Thanks for the tip on the iac. The only cleaner I have on hand is "super tech carburetor and air intake cleaner". It says it will not harm catalytic converters or oxygen sensors and contains no methylene chloride. Do you think that will be ok to clean the iac?

fragmental

If the throttle stays fully closed during idle, my guess is the iac got unstuck or unclogged in the process of the cleaning the throttle body. I should probably take the whole thing off and clean it all thoroughly. I used to deliver newspapers to racks and it involved idling the car alot. I suspect the sticky iac was the cause of the my really terrible fuel mileage, as well as some of the other problems I was having. I don't remember exactly what they were, but iirc they were somehow involved with idling, or overheating, or both.